产后出血是指胎儿娩出后24 h内失血量超过500 ml,是分娩期严重的并发症。发生的原因主要有子宫收缩乏力性出血、胎盘因素出血、软产产道裂伤出血、凝血功能异常出血等,其中以子宫收缩乏力性产后出血占首位,占产后出血总数的70%～80%〔1〕。剖宫产是产科的常见手术,剖宫产手术更易并发宫缩乏力 Postpartum hemorrhage refers to the loss of blood within 24 hours after delivery of the fetus more than 500 ml, is a serious complication of childbirth. The main causes of uterine atony bleeding, placental hemorrhage, soft birth canal laceration, abnormal coagulation bleeding, etc., of which uterine atony postpartum hemorrhage accounted for the first place, accounting for 70% to 80% of the total number of postpartum hemorrhage [ 1〕. Cesarean section is a common obstetric surgery, cesarean section surgery more easily complicated by uterine atony